Process for regenerating post-consumer and post-industrial fibers

ABSTRACT

Processes for producing regenerated fibers from post-consumer and post-industrial waste are disclosed. The process generally involves obtaining a source of post-industrial and/or post-consumer scrap material comprising fibers, cutting the material into a desirable size in the range of from one square inch to thirty square inches, detangling the fibers, removing any finish from the fibers, if present, combing and/or picking the fibers to convert any threads into fibers, humidifying the fibers, and intimately blending the fibers. These regenerated fibers can be blended with other fibers, and intimately blended to provide a uniform blend of fibers. The fibers can then be subjected to a carding process to orient the fibers. The regenerated fibers can be used in any application that would otherwise use virgin fibers, including their use to form woven or non-woven materials.

FIELD OF THE INVENTION

The present invention is generally in the field of regeneration ofpost-consumer and post-industrial fibers.

BACKGROUND OF THE INVENTION

Roughly a hundred billion pounds of post-industrial waste are landfilledor incinerated each year. While there are processes for recycling orregenerating these materials, such process traditionally providematerials used in lower value products such as carpet padding,automotive acoustic panels, and other items not visually impacted by a“shoddy fiber” technology. While these are good uses for pre or postindustrial waste streams, consumers want more sustainable products intheir everyday lives. The area of non-wovens, such as personal careproducts and household wipes, is a rapidly growing industry. There wouldbe a tremendous value associated with using fibers which have beenrepurposed through a regeneration process into such non-woven products,instead of using virgin materials. This is particularly true fordisposable products. The same is true of fibers that are spun intothread or yarn, and used to produce fabrics and other woven products.

Fibers that have been re-purposed using fiber regeneration technologycould potentially offer a better product, at a cost advantage, resultingin an overall sustainable product that is good for the planet,consumers, and producers alike. It is important to understand thedifference between traditional recycling and regeneration of textile orother waste streams. Recycling of textile or other fibers use equipmentthat is well known in the trade of “shoddy” fibers. This equipment whenused takes textile waste and creates a shorter, weaker and damagedfiber. The process that we are talking about in this methodology is onethat takes post consumer or post industrial “waste streams” andpreserves the integrity of the strength and the length of the fibers sothat they can be taken back to their original use or blended with othermaterials and enhance the characteristics of their original use.

It would be advantageous to provide new processes for regenerating andreusing the fibers present in post-consumer and/or post-industrialwaste. The present invention provides such processes, as well asproducts prepared using the processes.

SUMMARY OF THE INVENTION

A process for upcycling and transforming waste materials into valueadded consumer products is disclosed. The process adds characteristicsof the material that could not be otherwise afforded using traditionalvirgin components, and which are aesthetically pleasing and offer valueto a quality consumer product.

The process uses traditional fiber-handling equipment, but makesspecialized and unique changes to create environmentally-sustainingproducts. In one embodiment, the process provides regenerated fibersthat closely match virgin fibers, and which are obtained at a cost thatis significantly less than the cost of producing virgin fibers.

The process can use post-industrial or post-consumer waste streams asfeedstocks. The waste streams include fiber-containing materials, andthe fibers can be isolated from the waste streams and regenerated inorder to achieve maximum benefit from the fiber lengths, strengths, andother properties. The fibers can then be efficiently processed throughtraditional or modified woven or non-woven processes into finished rollgoods. The finished roll goods can then be converted into a variety ofconsumer products.

The process described herein takes us several steps forward relative toother processes, in that it eliminates soft threads and individualizesthe fibers, and due to this new process, it can be used to regenerateand upcycle to transform the hundreds of millions of pounds of wastethat would have otherwise found its way to a landfill or incinerator.

The process creates products that are superior in certain qualities andcharacteristics to those made from virgin materials, typically at lesscost, or in a cost competitive manner relative to processes using virginmaterials. Thus, the process can reduce the carbon footprint associatedwith producing the products, reduce water usage, and reduce the use ofchemicals by greater than 90% relative to processes using virginmaterials, thus creating a true sustainable product and process.

Representative post industrial or post consumer waste streams that canbe used as feedstocks include fabrics such as knits, for example,t-shirts, socks, undergarments; wovens, from items such as shirting,sheeting, bottom weight, denim, bedding, and upholstery; and non-wovens.These materials can be bleached white, or optically brightened or dyedfabrics, and can be used to increase value and reduce cost by using thematerials as they are to create a higher valued product without usingadditional bleaches or dye baths to achieve the same results. DyedCotton fibers or yarns are more expensive and take additional chemicalsand waste water which increases the carbon output, chemicals and waterusage, but these regenerated fibers have either been thru bleaching,optical brightening or dyeing processes and therefore to achieve thesame final results to not have to be bleached, optically brightened ordyed and can have a better cost basis for the manufacturer and the sameor better aesthetic value for the consumer. For example, a baby wipe canbe made with regenerated cotton from knits and wovens, where the cottonis already white, so no bleaching or optical brighteners are necessaryto add to this process. At the same time, creating a non-woven out of acolored fiber waste stream, such as denim, can result in a pale bluewiping cloth perfect for industrial or household non-wovens, without theneed for additional dyes or colorants, to create a value added productfor the consumer product arena. The use of black fibers from blackt-shirt waste streams can result in marl yarns which are the mostexpensive yarns in the industry and this is a product that isinexpensively, reduces carbon footprint, water and chemical usage by upto 90% and is a consumer's preferred choice.

In this process, to create a total value stream, it is advantageous torealize that all (i.e., 100%) of the fiber lengths created in thisprocess can be used to create value added products. The example above ofthe baby wipe is created from a median fiber length of typically0.50-0.95 while the longer fiber that is derived from this process cango back to creating yarns of the same count and strength that theoriginal garments virgin material was made from. For example, the trimfrom a t-shirt manufacturer can be regenerated and upcycled to createyarn and knitted fabric to go back into a t-shirt of equal quality.

In this process, to create a total value stream, it can be advantageousto realize that all (100%) of the fiber lengths created in this processcan be used to create value added products. The example above of thebaby wipe is created from a median fiber length of typically 0.50-0.95inches, while longer fibers derived from this process can used to createyarns of the same count and strength that the original garments virginmaterial was made from. For example, the trim from a t-shirtmanufacturer can be regenerated and upcycled to create yarn and knittedfabric to go back into a t-shirt of equal quality.

These materials typically include fibers that are either 100% cotton, orblends of cotton and various other fibers, such as polyester, viscose,rayon, lyocel, nylon, bamboo, polyolefins, and the like.

The process can also incorporate other fibers, including natural andsynthetic fibers, such as fibers from seeds, stalks, basts, stems,leaves, or fruits, fibers derived from animal hair, and silk fibers orother protein based fibers. The other fibers can be transformed naturalfibers (i.e., cellulose derivatives), and wholly-synthetic fibers. Theother fibers can also include inorganic fibers, such as glass fibers andmetal fibers.

At least a portion of the fibers are isolated from post-industrial orpost-consumer waste. To isolate fibers from these materials, which arepreviously woven, knitted, or bonded together by a non-wovens process,it is necessary to un-weave or un-twist the threads. This can beaccomplished, for example, by removing post-treatments from the threads,which thins the threads and loosens the knots or twists. In the case ofcellulosic fibers, a portion of the cellulosic fiber can be degraded,for example, using a cellulose enzyme. Once the threads areunwoven/untwisted, the fibers are obtained by combing the thread, whichproduces fibers that have maintained the length and the strengthnecessary to go back to textiles or, in this embodiment, non-wovens.

Before going into woven or non-woven materials, it can be advantageousto pass the fibers through one or more stages of “intimate blending,” sothat the fiber distribution is relatively homogeneous. The term“relatively homogeneous” is used to mean that the average fiber size anddensity varies by 20% or less throughout the fiber. The intimateblending can also provide color uniformity, which can otherwise bedifficult to attain when different batches of fibers are used to producea single non-woven fabric.

Intimate blending involves initially humidifying or treating the fibers,which strengthens the fibers, if they are organic fibers such as cotton,cotton blends or fibers such as rayon or ramie, reduces dust particlesfor better product performance and, protecting the fibers from tensileelongation, and reduces neps. The fibers can be humidified, for example,by exposing them to steam, contacting them with a hydrophilic compoundsuch as glycerol/glycerine, a surfactant, water, and the like. Ideally,the humidified fibers have a moisture content of between 8 and 20%moisture, more ideally, between about 8 and about 12% moisture. Then,the fibers can be passed through one or more blending stages, wheresamples from multiple hoppers are blended together to reduce variationbetween the fibers in the hoppers, or where samples from a single hopperare blended to ensure consistency in the hopper or it could be blendedusing a traditional cotton/fiber laydown where bales are staged forblending. Multiple hoppers can be used, for example, where blends ofdifferent fibers are intended. Examples include using regenerated cottonfibers in combination with one or more virgin or regenerated plantfibers, such as wood, kenaf, and the like, or synthetic fibers, such aspolyester or polyolefin fibers. However, the regenerated cotton fiberscan be used by themselves, without adding other fibers.

The fibers at this stage in the process are randomly oriented, but canoptionally be oriented using a non-woven or textile carding process.

The fibers can be subjected to one or more chemical treatments,Representative treatments include humidification, the addition ofsurfactants to provide more hydrophilic products, which can be importantwhen the fibers are used to prepare wipes or other substrates used inaqueous solutions, or when the fibers are used in substrates needing tobe used to absorb liquids. Other such treatments include treatment withstarch, glycol/glycerin, antimicrobial agents, such as cationicpolymers/cationic latex, silicones, fluorinated agents which provide thefibers and resulting materials formed from the fibers with anti-stainprotection, and the like. These treatments can occur after the fabrichas been formed, or before the fibers are formed into thread andknitted, and/or mechanically/thermally/chemically bonded in non-wovenprocesses.

In one embodiment, the randomly-oriented, intimately blended fibers aresubjected to a carding process to form a uniform fiber web. Such auniform fiber web is typically passed, over a conveyor belt or a web,where it can optionally be combined with one or more layers of fibers orwebs of fibers.

The regenerated fibers can be used in processes where they are layeredwith one or more layers of fibers that are different fibers than theregenerated fibers. The additional one or more layers can compriserandomly-oriented fibers, for example, laid down in an air-laid processover the top of the oriented fiber web, and, optionally, a furtheroriented fiber web can be laid on top of the randomly-oriented fibers.

In another embodiment, these fibers can be taken from the baled stockproduced after the regeneration process, entered into a spinning milleither on the “lay down” of cotton in the blow room or placed into thetextile mill thru a blending hopper and metered feeding system thru thecarding process to create sliver and then continued down the mill floorto be spun into high quality yarns that maintain all efficiencies ofvirgin fibers. These can be used at 100% regenerated fibers or a blendof virgin cotton or other textile related fibers such as rayon, lyocel,polyester and the like.

In other embodiments, the regenerated fibers are combined withpolyolefin or other thermoplastic fibers, so that the fibers can bebonded in a thermal fashion, rather than a chemical or mechanicalfashion, when used in non-woven applications. In this embodiment, thethermoplastic fibers are typically present in a concentration of atleast around 5% w/w.

In one embodiment, a cationic wet-strength resin is applied to thefibers, for example, via dipping, spraying, and the like, to impartadditional strength to the fibers, for example, when they are used inwet-laid applications to form wipes or other products.

The regenerated fibers can find use in a number of end-products,including knits, woven and non-woven products. Woven products includetextiles, rugs, apparel, and the like. Examples of some of the potentialnon-woven products include, but are not limited to, hygiene products,medical products, filters, geotextiles, and other products, andspecifically include wipes. The wipes can be adapted to include avariety of additional components, including moisturizers, cleansers,essential oils, antibacterials, antivirals, antimicrobial cationicpolymers, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a carding device.

DETAILED DESCRIPTION

The regeneration process is described in detail below. The processdescribed herein generally involves recovering fibers frompost-industrial or post-consumer waste, optionally blending those fiberswith other fibers, optionally subjecting the fibers to an “intimateblending” step to provide a uniform blend of fibers. The fibers can thenbe subjected to a carding process to orient the fibers. Optionally, thefibers can be subjected to one or more chemical treatments, and can bespun into yarn or thread, and used to make woven products, or useddirectly in non-woven products. Each of the process steps is describedin more detail below.

The present invention will be better understood with reference to thefollowing definitions:

DEFINITIONS

As described in more detail herein, fibers are formed into a web using avariety of processes, which include techniques for a) orienting or notorienting the fibers, b) laying the fibers down to form a web, and c)bonding the fibers in the web to form a non-woven material. Cardingprocesses are typically used to orient the fibers. The fibers can belaid down on a moving conveyor belt using a variety of techniques,including direct carding lay, air carding, air lay, wet lay, and thelike. The laid-down fibers can then be bonded using one or more ofmechanical, chemical, or thermal bonding techniques. Terms of art inconnection with the laying down of fibers, and the bonding of thelaid-down fibers, are defined below.

Textile Yarns

Yarn is defined herein as a long continuous length of interlockedfibers, suitable for use in the production of textiles, sewing,knitting, weaving and ropemaking. Yarn can be made from any number ofsynthetic or natural fibers. Very thin yarn is referred to as thread.Yarns are made up of any number of plys, each ply being a single thread,with these threads being twisted (plied) together to make the finalyarn.

Textile Fabrics:

As used herein, a “textile fabric” refers to any material made throughweaving, knitting, crocheting, or bonding. The term “cloth” refers to afinished piece of fabric that can be used for a purpose, such ascovering a bed.

Non-Woven Fabric

As used herein, a “non-woven fabric” is defined as a fabric madedirectly from a web of fiber, without the yarn preparation necessary forweaving and knitting. In a non-woven, the assembly of textile fibers isheld together 1) by mechanical interlocking in a random web or mat; 2)by fusing of the fibers, as in the case of thermoplastic fibers; or 3)by bonding with a cementing medium such as starch, casein, rubber latex,a cellulose derivative or synthetic resin. Initially, the fibers may beoriented in one direction or may be deposited in a random manner. Thisweb or sheet is then bonded together using a variety of methods, whichare described in detail below.

Various techniques can be used to prepare the initial assembly oftextile fibers, including air carding, direct lay carding, air lay, andwet lay.

Carding

As used herein, “carding” is a mechanical process that breaks up locksand unorganized clumps of fiber, and then aligns the individual fibersso that they are more or less parallel with each other. These orderedfibers can then be passed on to other processes that are specific to thedesired end use of the fiber. Carding can also be used to create blendsof different fibers or different colors. When blending, the cardingprocess combines the different fibers into a substantially homogeneousmix. Commercial cards commonly have rollers, and may optionally havesystems in place to remove various contaminants from the fibers.

Commercial carding machines allow the “carded” fiber to pass through theworkings of the carder for storage or for additional processing by othermachines. A typical carder has a single large drum (called the “swift”)accompanied by a pair of in-feed rollers (“nippers”), one or more pairsof worker and stripper rollers, a “fancy,” and a “doffer.” In-feed tothe carder is usually accomplished by conveyor belt, and often theoutput of the carder can either be stored as a batt, or furtherprocessed into the non-woven material described herein by mechanically,chemically, or thermally bonding the fibers together. A representativecarder is shown in FIG. 1. in FIG. 1, raw fiber, placed on an in-feedtable or conveyor, is moved to the nippers (30) which restrain and meterthe fiber onto the swift (10). As they are transferred to the swift,many of the fibers are straightened and laid into the swift's cardcloth. These fibers will be carried past the workers (40)/stripperrollers (20) to the “fancy” (50).

As swift (10) carries the fibers forward from the nippers (30), thosefibers that are not yet straightened are picked up by a worker (40) andcarried over the top to its paired stripper (20). Relative to thesurface speed of the swift (10), the worker (40) turns quite slowly.This has the effect of reversing the fiber. The stripper (20), whichturns at a higher speed than the worker (40), pulls fibers from theworker (40) and passes them to the swift (10). The stripper's relativesurface speed is slower than the swift's, so the swift (10) pulls thefibers from the stripper (20) for additional straightening.

Straightened fibers are carried by the swift (10) to the fancy (50). Thefancy's card cloth is designed to engage with the swift's card cloth sothat the fibers are lifted to the tips of the swift's card cloth andcarried by the swift (10) to the doffer (60). The fancy (50) and theswift (10) are the only rollers in the carding process that actuallytouch.

The slowly turning doffer (60) removes the fibers from the swift (10)and carries them to a fly comb (not shown) where they are stripped fromthe doffer. A fine web of more or less parallel fiber, a few fibersthick and as wide as the carder's rollers, exits the carder at the flycomb by gravity or other mechanical means. The web can then be stored,or further processes into a non-woven material using the additionalprocess steps described herein.

A carder typically includes a “card cloth.” A card cloth is made from asturdy rubber backing, in which closely-spaced wire pins are embedded.The shape, length, diameter, and spacing of these wire pins is dictatedby the card designer and the particular requirements of the applicationwhere the card cloth will be used.

Card Room

The carding step is typically conducted in a room, called a “card room,”which is set up to handle the carding equipment, and also to provide theappropriate temperature and pressure for the fibers, in order tomaintain their length and strength throughout the carding process.

Moisture Requirements:

In order to maintain the length and strength of the fibers, it ispreferred to control the moisture content of the fibers as they arecarried out through the various process steps. Ambient temperature(i.e., around 75° F.) is ideal, and a relative humidity of around 65% isalso ideal, although these can vary, according to each individualnon-woven product being created, and the ranges of regenerated fibers ineach product.

In one embodiment, the product includes relatively high percentages ofregenerated cotton fibers, and therefore requires relatively higherhumidity. The ranges of temperature and humidity are ideally within thefollowing parameters: temperature between 62 and 98° F. and relativehumidity between 40 and 90 percent.

Modification of Textile Carding and Spinning Equipment

While the fibers have the length and strength requirements found innatural virgin fibers, there can be dust associated with the fibers thatare a bit smaller than that of traditional fibers thereforemodifications must be considered in further carding, drawing, roving andspinning equipment. It is typical in this process that additionalcleaning, with light suction points throughout the equipment, can beused to maximize the performance of these fibers.

Filtration Points in Non-Woven Web-Forming Equipment

Due to the short staple that is inherent in regenerated fibers, theremay be dust particles that accompany the fiber throughout theregeneration process. In order to efficiently use regenerated fibers, itcan be desirable to remove the dust particles. One way to do this is tomodify traditional equipment running synthetic fibers, so that the dustparticles are removed, and the regenerated cotton fiber can be run ataround the same efficiencies as that of synthetics. If the dustparticles are not removed, the dusting can cause problems withequipment, such as shut downs or overheating.

One such modification involves placing “suction points” throughout thecarding equipment to insure cleanliness of motors, drives, webformation, and the like. These “suction points” can remove the dust, andeliminate or minimize the problems associated with dust particles.

Card Wire Specification: If a non-woven card is used in the process ofweb formation, it can be important that the proper metallic toothwire isused that is specific to the raw material requirements. In oneembodiment, the issue relates to the ability to successfully manufacturea non-woven product with high percentages of regenerated cotton. Whenseeking to regenerate cotton fiber, it can be advantageous to use ametallic toothwire that is specific to use with cotton fibers. Forexample, while there are many producers of wire specific to cotton, JDHollingsworth is a manufacturer of card clothing that has a number ofpatents around the appropriate wire for cotton. While they focused theirresearch on virgin cotton, the points on the wire are similar, since theregeneration of the fiber returns the cotton back to its originallengths and strengths.

The points are thus relevant to forming the highest quality regeneratedfibers, and the use of the appropriate points is a preference in themanufacturing of a high regenerated cotton product as this embodimentdescribes. It is not always necessary to use a card clothing/wirespecific to cotton, but it is preferred. There are other wires specificto synthetics, and these have a much broader range of options.

I. Origin of Regenerated Fibers

In one embodiment, the regenerated fibers are recovered and regeneratedfrom fabrics such as knits, including t-shirts, socks, andundergarments; wovens, including items such as shirting, sheeting,bottom weight, denim, bedding, and upholstery; and non-wovens.

These fibers typically include one or more of the following: 100%cotton, cotton blends, such as cotton/polyester, cotton/viscose,cotton/lycra, cotton/ramie, cotton/nylon, and the like, viscose/rayon,polyester, polypropylene or other polyolefins, nylon or otherpolyamides, and ramie.

II. Additional Fibers that can be Added

In addition to the fibers described above, other fibers can also beused. Representative other fibers include natural, organic, andsynthetic fibers.

Natural fibers include those from various plants/vegetables. Examples offibers derived from seeds include cotton and kapok (KP).

Examples of fibers derived from basts or stems include wood, flax, linen(LI), hemp (HA), sunn hemp (SN), jute (JU), ramie (RA), kenaf (KE),straw (STR), banana (BAN), pineapple (PIN), papyrus (PAPY),alfagras/esparto (AL), fique/Mauritius Fiber (FI), alginate (ALG),urena/Congo Jute (JR)), nettle (NTL), broom (GI), apocynum (APO), raffia(RAF), and natural bamboo (BAM).

Examples of fibers derived from leaves include sisal (SI), abaca/Manila(AB), henequen (HE), phormium/New Zealand Fiber (NF), acacia (AKAZ),aloe (ALO), yucca (YUCC), and elephant grass (ELEG).

Examples of fibers derived from fruit include coir/coconut (CC).

Animal fibers include wool and other animal hair (WO), silk (SE), andwild silk/Tussah (ST).

The fibers can be formed by various transformations of natural fibers,for example, regenerated cellulose & cellulose esters such as viscose(CV), bamboo regenerated (CBAM), modal (CMD), lyocell (CLY), acetate(CA), and tri-acetate (CTA).

Examples of proteinaceous fibers derived from plants include peanut(PEA), corn (COR), soybean (SPF), alginate (ALG), milk (CS), andpolylactic Acid (PLA).

Examples of fibers formed from synthetic polymers include polyamides,such as Polyamide 4.6 (PA 4.6), Polyamide 6 (PA 6), Polyamide 6.6 (PA6.6), Polyamide 6.10 (PA 6.10), Polyamide 6.12 (PA 6.12), Polyamide 11(PA 11), Polyamide 12 (PA 12), and Polyamide-imide (PAI). Also includedare polyesters, such as polyethylene terephthalate (PET), polycyclohexane-dimethanol terephthalate (PCT), polytrimethyleneterephthalate (PTT), polybutylene Terephthalate (PBT), polyestermide(PETI), and polybeta hydroxybutyrate (PHB). Representative polymers alsoinclude polyurethanes (PU), including polyuretherthane (PUR), elasthane(EL), and elastodiene (ED). Also included are polyvinyl compounds,including polyvinyl chloride (CLF), polyvinylidene fluoride (PVDF),polyvinylidene chloride (PVDC), polyvinyl alcohol (PVA), polyvinylacetate (PVAC), and ethlyene vinyl acetate (EVA). Polyolefinic fibersinclude polyethylene (PE) and polypropylene (PP). Some of these fibersare fluorinated, such as polyteteafluorethylene (PTFE), ethylenechlorotrifluorethylene (ECTFE), polychlorotrifluoroethylene (PCTFE),perfluoroalkoxy (PFA), and polyvinyl fluoride (PVF). Other syntheticfibers include meta-aramid (m-AR), para-aramid (p-AR), melamineformaldehyde (MF), polybenzimidazole (PBI), polycarbonate (PC),polyetheretherketone (PEEK), polyether-imide (PEI), polyetherketone(PEK), polyethersulfone (PES), polyethyleneaphtalate (PEN), polyimide(PI), polymethyl methacrylate (PMMA), polyoxymethylene or polyacetal(POM), polyphenylene oxide (PPO), polyphenylenesulfide (PPS),polystyrene (PS), and polysulfone (PSU).

Some fibers are inorganic in nature. Representative inorganic fibersinclude glass fiber (GF), silicic acid glass (GFS), carbon fiber (CF),ceramic fiber (CEF), metallic fibers (MTF), steel (STL), inox (INX),copper (CU), and basalt (CBF).

Representative Fiber Lengths

In the world of regenerated fibers, there are typically three lengthsthat are considered. The longer length is best used in cardedapplications, medium length fibers used in both carded and air laidapplications, and short fibers are more specific to air laid or wet layprocesses. Fiber lengths can range from 50 microns to up to 6 inches ormore for crimped or non-crimped fibers.

For both the regenerated fibers (isolated from post consumer and/orpost-industrial waste), and the other fibers, suitable fiber lengths anddistribution can vary from fibers as small as 250 microns to fibers upto 6 inches, based on the delivery mechanism.

An example of lengths of fibers necessary to a wet laid applicationwould be 250 microns to 13 mm, where the fiber lengths in a dry directlay application would vary from 0.50 median lengths up to 3 inches.

In one embodiment, the fibers are regenerated cotton fibers, with a sizerange between about 250 microns to about 8 mm for wet laid applications,and between about half inch and about 1.30 inches for dry direct lay ora combination of direct lay and air carding application.

For example, where a “direct lay with air card for randomization”approach is used, the range is most effective between about 2 mm inchand about 1.30 inch. The ranges for the fibers depend, at least in part,on the desired application for the non-woven material.

When regenerated fibers are used in combination with other fibers, theregenerated fibers are preferably present in a concentration of betweenabout 2 and about 98%, and the other fibers are preferably present in ana concentration of between about 1 and about 88%, based on the totalweight of the fibers. In one embodiment, the blend of regenerated fibersand other fibers is a 95/5 blend by weight. In another embodiment, theblend of regenerated fibers and other fibers is a 90/10 blend, a 85/15blend, and 80/20 blend, and 75/25 blend or 50/50 blend. In these blends,the other fibers can include any of the other fibers described herein,in any desirable combination.

III. Process for Isolating Fibers from Post-Consumer or Post-IndustrialWaste

Ideally, the process for isolating fibers from post-consumer orpost-industrial waste involves using needles to separate thepreviously-woven strands into the threads that comprised the fabric tobegin with. As this is difficult to do with the entire scrap material,it is advantageous to cut the scrap into a more manageable size (i.e., auniform 2″ by 2″, 4″ by 4″, or other suitable size). It can also help towork from the ends of the scrap material, rather than the middle of thescrap material.

In some embodiments, the fibers are cellulosic fibers. It can beadvantageous to slightly degrade the fibers, so that they are not astightly knitted or woven. That is, by degrading a portion of thecellulose, the knots open up slightly, making it easier to unravel theknots and obtain the free threads.

Cellulose fibers can be degraded by contacting them with variousenzymes, which enzymes include cellulases. One or a combination of suchenzymes can be used. Cellulosic and other fibers typically have one ormore post-treatments on them, which thicken the fibers. Enzymatic orchemical processes can be used to remove the post-treatments, thusthinning the fibers and loosening the knots or weaving.

Contact times and temperatures for the enzymatic or chemical processescan be determined using ordinary skill, for example, by monitoring thepartially-degraded material to determine the optimum point in time wherethe threads are loosened enough to un-knit them, but not so much that asignificant loss of material is observed. Ideally, the temperature isbetween 120 and 180° C., although these reactions can also occur atlower temperatures, such as room temperature.

After the threads are un-knitted, loose threads can be stored for lateruse. In some embodiments, it can be useful to remove any dyes from thethreads, so that the threads resemble virgin material.

In order to process the threads into a non-woven material, it can beadvantageous to “fluff” the threads into a lower density material, wherethe density is reduced relative to the original fibers, or clumps offibers, obtained from the de-knitting process. Fluffing is generallyaccomplished using a mechanical combing and/or picking action, whichselects smaller quantities of threads from the whole, and the combingand/or picking action breaks the threads down into lint or individualfibers.

The fibers or lint produced in the fluffing step are in randomorientation, and in certain non-woven applications, it is desired toorient the fibers in a single direction. This can be accomplished, forexample, using a modified carding operation. In a modified cardingoperation, a series of cylinders are used, where a comb is aligned withthe cylinders. The fluffed fibers are passed over the cylinders, incontact with a plurality of combs, which orient the fibers. Once thefibers are oriented, they are suitable for use in preparing non-wovenmaterials, particularly where the oriented fibers are intended to bemechanically interwoven, such as with a spun-lace process.

To isolate fibers from these materials, which are previously woven,knitted, or bonded together by a non-wovens process, it is necessary toun-weave or un-twist the threads. This can be accomplished, for example,by removing post-treatments from the threads, which thins the threadsand loosens the knots or twists.

In the case of cellulosic fibers, a portion of the cellulosic fiber canbe degraded, for example, using a cellulose enzyme, and such enzymes areknown in the art, and sold, for example, by companies such as Iogen andNovozymes.

Once the threads are unwoven/untwisted, the fibers are obtained bycombing the thread, which produces fibers that have maintained thelength and the strength necessary to go back to textiles or, in thisembodiment, non-wovens.

Before going into textiles or non-wovens, it can be advantageous to passthe fibers through one or more stages of “intimate blending,” so thatthe fiber distribution is relatively homogeneous. The terms “relativelyhomogeneous” or “substantially homogeneous” are used to mean that theaverage fiber size and density varies by 20% or less throughout thefiber. The intimate blending can also provide color uniformity, whichcan otherwise be difficult to attain when different batches of fibersare used to produce a single non-woven fabric.

IV. Intimate Blending of the Various Fibers

In one embodiment, the fibers are subjected to an intimate blendingprocess step. Intimate fiber blends are described herein assubstantially homogeneous blends of fiber(s) that distribute thedifferent lengths or different combinations of the fiber(s) evenlythroughout the batch of fiber. The regenerated cotton non-woven fabricdescribed herein is ideally prepared using intimate blending, to ensurehomogeneous fiber distribution, due to the broad range of fiber lengthsfound in regenerated fibers. It is also ideally prepared using fiberhumidification to maintain the strength of the fiber throughout theprocess, as well as using suction points and/or a filtration system tokeep the equipment running efficiently, by removing dust particles andthe like.

This intimate blending can contribute to the beneficial properties ofthe regenerated fiber substrate. The fiber distribution in regeneratedtextiles can be varied, and, accordingly, intimate blending of theresulting fibers can be performed, whether the fibers are used alone oras blends with other types of fibers, prior to entanglement or fusion.The use of other fibers is optional, and depends on the desiredapplication of the resulting non-woven fabric.

Intimate blending involves initially humidifying or treating the fibers,which strengthens the fibers, if they are organic fibers such as cotton,cotton blends or fibers such as rayon or ramie, reduces dust particlesfor better product performance and, protecting the fibers from tensileelongation, and reduces neps.

The fibers can be humidified, for example, by exposing them to steam,contacting them with a hydrophilic compound such as glycerol/glycerine,a surfactant, water, and the like. Ideally, the humidified fibers have amoisture content of between 8 and 20% moisture, more ideally, betweenabout 8 and about 12% moisture. Then, the fibers can be passed throughone or more blending stages, where samples from multiple hoppers areblended together to reduce variation between the fibers in the hoppers,or where samples from a single hopper are blended to ensure consistencyin the hopper or it could be blended using a traditional cotton/fiberlaydown where bales are staged for blending. Multiple hoppers can beused, for example, where blends of different fibers are intended.Examples include using regenerated cotton fibers in combination with oneor more virgin or regenerated plant fibers, such as wood, kenaf, and thelike, or synthetic fibers, such as polyester or polyolefin fibers.However, the regenerated cotton fibers can be used by themselves,without adding other fibers.

The following is a general process for intimately blending fibers,though not every step needs to be carried out exactly as describedbelow, so long as the resulting fiber distribution is substantiallyuniform.

Bales of regenerated fiber are taken and put into large storage hoppersbased on each individual fiber type. If the blend is 100% of one fiber,then the hoppers deliver by weigh pan methods exactly or substantiallythe same percentage of fiber out of each hopper. If the percentages ofeach fiber are different, then the bales are put into the hoppers, and,using weigh pan technology, the fiber is delivered onto a belt with each“group” of fibers being laid on top of one another.

The “groups” of fiber are then put into a “fine opening” process, whichcarefully blends the fibers together and deposits them to the next stageof blending, which begins with a large storage hopper. In oneembodiment, the hopper holds up to 40,000 lbs of fiber.

As the fiber passes through the air into the box, this provides anotheropportunity to blend the fibers, and also affords the opportunity toprovide additional humidification or fiber treatments.

When the storage hopper is full or substantially full, the fibers canthen be picked, for example, using a sandwich-like approach where thefibers are laid down horizontally into the blending hopper in layersthen vertically picked up from the bottom to the top of the hopper,using a spiked apron and a moving floor, and put into yet another fineopener which takes the fibers delivered from the blending hopper andgently opens and fluffs the fibers before delivering the fibers to bebaled for further processing, or directly into the specific applicationused to deliver the fibers to their entanglement or fusion process.

Carding

After the fibers are intimately mixed, a card wire can be used to openand gently align the fibers, to maintain a consistent web appearance.When the fibers are regenerated cotton fibers, or predominantly so(i.e., greater than about 50% regenerated cotton fibers, or regeneratedand virgin cotton fibers), the resulting web has using the unique lookand feel of cotton. The carding process can also be used in thoseembodiments where intimate mixing is not performed, before the non-wovenweb is produced.

V. Fiber Treatments

Ideally, to ensure that the cotton fibers maintain their length andstrength during the regeneration process, and to maximize regeneratedcotton fiber processability, the fibers are humidified. In oneembodiment, cotton fibers are delivered to the blending process with noless than 8%, but no greater than 25%, moisture content. This moisturelevel increases the fiber strength, and therefore preserves the fiberlength.

It is also desirable to keep moisture levels in the fiber throughout theprocess, which can be done, for example, by adding humectants or othersuitable materials (i.e., hydrophilic materials such as glycerol) to thefibers.

The moisture level throughout the process ideally does not drop below5%, and in one embodiment, levels out to between 12 and 15% at the endof the process.

The fibers can also be subject to other fiber treatments, either beforeor after forming the fibers into a non-woven material. Representativefiber treatments include one or more of humidification, addition ofsurfactants to provide the fibers with greater hydrophilicity (forexample, when the fibers are used for highly hydrophilic products, suchas wipes or other substrates used in aqueous solutions or a substrateneeding to be used to absorb liquids). Other representative treatmentsinclude, but are not limited to, starch, glycol/glycerin, antimicrobialtreatments, silicone, fluorinated anti-stain treatments, addition offire retardants, addition of cationic wet strength resins, and the like.

Representative wet strength resins include the cationic polyamide wetstrength resins sold by Georgia Pacific® under the Amres® brand, and aretypically supplied as aqueous solutions in a range of solids from 12.5%to 35%, and include Amres® 117, Amres® 12-HP, Amres® 135, Amres® 20-HP,Amres® 25-HP, Amres® 652, Amres® 653, Amres® 8855, Amres® 8860, Amres®8870, Amres® HP-100, Amres® HS-30, Amres® MOC-3025, Amres® MOC-3066,Amres® PR-247HV, and Amres® PR-335 CU.

VI. Processes for Laying Down Fibers

To form a non-woven sheets, which are typically then rolled to form arolled good, one first orients the fibers in a desired manner, then laysthe fibers down onto a conveyor belt to form a web, and thenmechanically, chemically, or thermally bonds the fibers in the web. Thefibers can be laid down using one or more processes as are well known inthe art of non-wovens, including direct lay, wet-lay, and air-layapproaches.

In some embodiments, layers of webs formed from the fibers can becombined. For example, the non-woven material can include a) multiplecarded webs, b) a direct carded layer on which an air laid layer and asecond direct carded layer are applied, c) cross-lapped layers, and d)layers combined with a scrim.

By using these approaches, one can provide a regenerated cotton productwith the MD/CD strengths that are gained from much longer syntheticfibers. By using one or more carding groups based on weight calculationof the desired product, one can add an air carded web that is a totalrandomization of fibers, creating MD/CD ratios of the most sought after1-1 strength requirements.

By adding an air carded web in the center of three carding groups, theaesthetics are that of a complete carded web product, with the strengthof synthetic fibers (particularly when the air carded web includesrandomly oriented synthetic fibers), while still using the more desiredsustainable cotton fibers (for example, in the direct laid top andbottom webs).

Cross-lapped products tends to be loftier than those produced using adirect-carded web, or even the above-described embodiment where a directlay approach is used with an air card layer to a layer with providerandomized fiber orientation.

The addition of a scrim layer provides yet another way to increase MD/CDstrength of a regenerated cotton web, where the added strength comesfrom the added scrim.

In any of these embodiments, the fibrous web can be bonded using knownmechanical, chemical, or thermal bonding techniques. Mechanical bonding,which involves interlocking the fibers into a random web, mat, or sheet.Thermal bonding involves fusing the fibers, for example, by addingbetween 2 and 20% of a thermoplastic fiber, for example, a polyolefin(such as polypropylene) fiber. When heated, such as between calendarrolls, one can fuse the fibers together. Chemical bonding involvesadding a cementing medium to the fibers, and chemically fusing thefibers together. Representative cementing media include starch, casein,rubber latex, cellulose derivatives, and synthetic resins. A hybridchemical/mechanical approach that is occasionally used with cottonnon-wovens is to treat the web with sodium hydroxide, to “shrink-bond”the web. The caustic causes the cellulose-based fibers to curl andshrink around one another as the bonding technique. This approach can beadvantageously used with regenerated cotton fiber.

As discussed above, the fibers may be oriented in one direction or maybe deposited in a random manner to form a web or sheet, using thevarious processes for laying down the fibers. This web or sheet can thenbe bonded together by one of the methods described above. The presentinvention is intended to encompass non-wovens prepared using randomand/or oriented fibers, laid down with any of the above-mentionedtechniques, and bonded using any of the above-mentioned techniques, inany combination.

Representative bonding methods include thermal bonding, using a largeoven for curing, calendering through heated rollers (called spunbondwhen combined with spunlaid), wherein the calendars can be smooth facedfor an overall bond or patterned for a softer, more tear resistant bond,hydro-entanglement (the mechanical intertwining of fibers by water jets,called “spunlace,” ultrasonic pattern bonding, often used in high-loftor fabric insulation/quilts/bedding, needlefelt (mechanical intertwiningof fibers by needles, and chemical bonding (a wetlaid process involvingthe use of binders, such as latex emulsion or solution polymers, tochemically join the fibers). A more expensive route uses binder fibersor powders that soften and melt to hold other non-melting fiberstogether. Some of the non-woven fabrication methods that can be used toprepare the non-woven materials described herein are described in moredetail below.

In any of the above-mentioned techniques, the resulting bonded web ormat is then either used directly to form finished goods, or can berolled-up and stored for later conversion to finished goods.

VIII. Materials Formed from the Non-Woven Fabric

The non-woven materials produced using the methods described herein canbe used in numerous applications, including hygiene products, medicalproducts, filters, geotextiles, and other products. Representativehygiene products include baby diapers, feminine hygiene products, adultincontinence products, wipes, including anti-septic wipes, bandages andwound dressings. Representative medical products include isolationgowns, surgical gowns, surgical drapes and covers, surgical scrub suits,and caps. Representative filters include gasoline, oil and air filters,including HEPA filtration, water, coffee, and tea bags, liquidcartridges and bag filters, vacuum bags, allergen membranes, andlaminates with non woven layers. Representative geotextiles include soilstabilizers and roadway underlayment, foundation stabilizers, erosioncontrol, canals construction, drainage systems, geomeambranesprotection, frost protection, agriculture mulch, pond and canal waterbarriers, and sand infiltration barriers for drainage tile. Otherproducts include both primary and secondary carpet backing, composites,marine sail laminates, tablecover laminates, chopped strand mats,backing/stabilizer for machine embroidery, packaging—to sterilizemedical products, insulation (fiberglass batting), pillows, cushions,and upholstery padding, batting in quilts or comforters, consumer andmedical face masks, mailing envelopes, tarps, tenting and transportation(lumber, steel) wrapping, and disposable clothing (foot coverings,coveralls).

The production of the various materials described above from a non-wovenfiber roll good can be done using methods well known to those of skillin the art.

IX. Spinning and Weaving Processes

When it is desired to convert the fibers into woven materials, thefibers are first converted to yarn or thread using spinning processes,as such as known in the art. There are many variables in a spinningmill, including the types of fibers to be spun, atmospheric conditionsin the plant, type of machines, market requirements, and the like. Thoseof skill in the art can readily control these variables to produce aquality yarn or thread using the regenerated fibers described herein.

X. Finished Woven Goods

The yarn or thread spun from the regenerated fibers, or combinations ofregenerated and other fibers, can be used to create woven fabrics, whichcan be used directly or can be stored for later use. The thread and yarncan optionally be dyed or bleached using conventional techniques, andtreated with any of a variety of treatments to impart beneficialproperties, as described above with respect to the fibers and thenon-woven fiber rolls. The woven fabrics can be used to prepare any of avariety of textiles, clothing, and the like. The production of thevarious materials described above from a woven fabric can be done usingmethods well known to those of skill in the art.

XI. Representative Conditions and Process Steps

In one embodiment, the regeneration process involves:

1. Collecting the raw material that is of consistent composition.

2. Cutting the waste raw material into manageable sizes to open theappropriate lengths desired by the end use application,

3. Using sword sharpened 1-4 inch pinning to separate the groups ofthreads from each other,

4. Using a chemical treatment, optionally using specific enzymes andspecific fabric softeners to take off any “textile” finish that iscreated in the textile manufacturing process, ideally at a temperatureabove room temperature, but below the boiling point of water,

5. Allowing a residence time in the chemical treatment of at least 1-24hours dependent on the end use application,

6. Removing the textile material from the residence area into multipleuntwisting chambers, accompanied with steam application in each chamberto keep the fibers from becoming damaged by heat or lack of moisture,that delicately separate the threads to create a final product of softtwisted yarns that are comparable to that of virgin materials in theirstrength, length and ability to dye of re-finish in traditional textileapplications.

The traditional method of re-cycling leaves fibers in a “shortenedfiber” state along with twisted yarns that are commonly called out asshoddy fibers used in automotive insulation, under carpet padding, andother low quality applications. The finishing method that is describedis used in combination with the regeneration technology describedherein.

The regenerated fibers are prepared as described herein. Material istaken in the soft twist state and air conveyed into a traditionaltextile machine that has been re-engineered to comb the fibers in atleast four different stages in the operation. The cylinders aredifferent sizes, with different combing wires and pin applications, tocreate a finished product that is comparable to cleaned virgin fibers.The fiber lengths have now been increased from the common recyclingmethods, to be used in a number of different applications.

The longer fibers can be spun into quality yarns, with counts from toequal or be greater than the quality of fiber or yarn count than that ofthe virgin material with no loss of strength to the final product andincreased hand and drape than what is seen from virgin materials. Theyarn can be carded or combed, single ply or multi ply and counts canrange from Single 4's to Single 60's or a multitude of Multi ply yarns.

These fibers preferably enter the cylinder machine with no less than 10percent moisture content, and ideally have a moisture content up toaround 30% moisture content. The materials are finished withapproximately 8-15% moisture content in the final product, with themoisture being dependent on downstream manufacturing choices. Themachines are held in a room with relatively high humidity, for example,greater than 50% relative humidity, and temperature typically between 70and 80° F., to maintain quality materials throughout the operation.

The present invention will be better understood with reference to thefollowing non-limiting examples.

Example 1 Process for Creating Regenerated Cotton Fiber

The following process was used to create regenerated cotton fiber, andcovers the process from raw material to finished roll goods producedfrom the fiber:

-   -   1. +/−40,000 lbs sorted cotton clips were gathered and collected        at textile cutting room locations, packaged and shipped to        regenerator location.    -   2. After complete inspection and receipt to regeneration        facility's warehouse, the cotton clippings were placed into a        robot loader for automatic bale opening and conveyed to        specialty cutters.    -   3. They were cut to targeted size of 2-4 in×2-4 in. These cut        pieces were transported by belt to the storage box where the        first blending of materials began.    -   4. The cut clips were transported via spike apron to a rotary        pin cylinder where they are pulled to untwist the fibers into        threads that comprised the fabric.    -   5. They were transported via air duct to another large storage        box where it was treated with a solution of a 2-6% cellulase        enzyme, surfactant, and/or a blend of enzymes and surfactants.        This solution removes any finishes, starches, etc from the        fiber. These fibers were treated for 12 hours for this process.    -   6. The treated pre-opened material is then transported by air        duct to a second box where it was passed through steam to        disinfect and deactivate the enzymatic treatment.    -   7. The material was then processed through a series of 5        modified cylindrical process pieces of equipment to continue        further opening of the material to a soft thread state. There        was an additional passing through steam after cylinder 2 and 4        to allow the moisture levels to be maintained and the fibers        were further untwisted from their original state.    -   8. The soft threads were then put into a bale and moved to an        intimate blending area.    -   9. The fiber was intimately blended using a laydown process with        the baled opened cotton fibers to create a homogeneous fiber        blend. The staging of the bales and the even distribution of        collecting fibers created the desired degree of fiber blending.    -   10. The blended fiber was transported via air duct to the        finishing line system that further untwisted the remaining soft        threads, while perfectly aligning the fibers and pulling out all        dust and shorter fibers to a secondary process.    -   11. Once processed through the regeneration fiber finishing        stage, the fibers were carried via air duct to the non-woven        blend area. Here the regenerated cotton fiber was further        blended together to ensure the lengths of fibers were consistent        throughout the batch using pre-feed hoppers, fine openers and        blending bins.    -   12. The regenerated cotton was then transported through a series        material transfer equipment without the use of fans but with the        use of vacuum to insure the quality of cotton when baled and        sent to it's final processes whether it be spinning into yarn        for knitted or woven fabrics, to a non-woven process, or further        engineering for paper or composite technologies.    -   13. The result was the following: Of the +−40,000 lbs, 60% or        +/−24,000 lbs of the fiber processed was applicable for textile        re-spinning based on the fiber characteristics, 25% or +/−10,000        lbs of the fiber processed was applicable for non-wovens based        on the fiber characteristics and 15% of the fiber processed was        applicable for use in cotton paper or composites.

UQL Mean SFC Neps Textile 1.19 1.00 13% 686 Non-Woven .95 .78 2% 686Paper/Composite .52 .37 0% NA

While the invention has been described in connection with the preferredembodiments and examples, it will be understood that modificationswithin the principles outlined above will be evident to those skilled inthe art. Thus, the invention is not limited to the preferred embodimentsand examples, but is intended to encompass such modifications.

1. A process for preparing regenerated fibers, comprising the steps of: a) obtaining a source of post-industrial and/or post-consumer scrap material comprising fibers, b) cutting the material into a size in the range of from one square inch to thirty square inches, c) detangling the fibers, d) removing any finish from the fibers, if present, e) combing and/or picking the fibers to convert any threads into fibers, f) humidifying the fibers, and g) intimately blending the fibers.
 2. The process of claim 1, further comprising carding the intimately blended fibers.
 3. The process of claim 1, further comprising forming a non-woven fiber roll good comprising the regenerated.
 4. The process of claim 3, further comprising converting the non-woven fiber roll good into a hygiene product, medical product, filter, or geotextile.
 5. The process of claim 1, further comprising spinning the fibers into a thread or yarn.
 6. The process of claim 5, further comprising weaving the thread or yarn into a woven fabric.
 7. The process of claim 6, further comprising converting the woven fabric into a finished woven good.
 8. The process of claim 1, wherein the regenerated fibers are blended with other fibers before or after the intimate blending process.
 9. The process of claim 8, wherein such other fibers are selected from the group consisting of fibers derived from plant matter, fibers derived from animal hair, silk fibers, protein-based fibers, transformed natural fibers, wholly-synthetic (organic) fibers, glass fibers and metal fibers.
 10. The process of claim 8, wherein the ratio of regenerated fibers to other fibers is between about 2/98 and 99/1.
 11. The process of claim 8, wherein the other fibers are selected from the group consisting of Tencel, Rayon, Lyocel, Polyester, polypropylene (PP), nylon, and PLA fibers.
 12. The process of claim 1, further comprising applying a post-treatment to the fibers, wherein the post-treatment is selected from the group consisting of starch, glycol/glycerin, antimicrobial treatments, silicone, fluorinated anti-stain treatments, fire retardants, and cationic wet strength resins.
 13. The process of claim 1, further comprising applying a treatment to the fibers, wherein the fibers are treated with starch, glycol/glycerin, antimicrobial agents, silicones, and fluorinated stain-resisting agents.
 14. The process of claim 1, wherein the regenerated fibers are cellulosic fibers, further comprising treating the fibers with a cellulase enzyme.
 15. The process of claim 1, where the intimate blending step comprises the intimate blending of two or more batches of regenerated fibers.
 16. The process of claim 1, wherein the regenerated fibers are blended with thermoplastic fibers, where the thermoplastic fibers are present in a concentration of at least around 5% w/w.
 17. The process of claim 1, further comprising baling the regenerated fibers.
 18. The process of claim 1, further comprising twisting the regenerated fibers into a yarn.
 19. The process of claim 1, further comprising twisting the regenerated fibers into thread.
 20. The process of claim 1, further comprising including the regenerated fibers in a paper-making process.
 21. The process of claim 1, further comprising using the regenerated fibers to form a composite material.
 22. The process of claim 1, wherein the regenerated fibers comprise black fibers from black t-shirt waste streams.
 23. The process of claim 23, further comprising weaving the regenerated black fibers into marl yarns. 